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Decentralized Linear Solvers: Communication Cost And Privacy, Nelson G. Brasil, Vinay A. Vaishampayan Jan 2026

Decentralized Linear Solvers: Communication Cost And Privacy, Nelson G. Brasil, Vinay A. Vaishampayan

Publications and Research

We consider the problem of multiple parties iteratively solving a system of linear equations in a decentralized manner. Specifically, we solve for $\negr{x} \in \R^n$, the $n \times n$ system of linear equations $M\negr{x} = \negr{b}$ when each party only knows their row of the matrix $M$ and a single component of $\negr{b} \in \R^n$. Our objective is to determine the tradeoff between the accuracy of the solution and the total communication cost measured in bits. A fully connected, reliable mesh network is assumed to connect the different parties. We develop a general formulation that applies to a large class …


Tempo: Training-Time Equilibration Of Modalities For Per-Sample Optimization In Multimodal Sentiment, Yi Zhao, Erik Cambria, Xiaosong E, Xianxun Zhu Jan 2026

Tempo: Training-Time Equilibration Of Modalities For Per-Sample Optimization In Multimodal Sentiment, Yi Zhao, Erik Cambria, Xiaosong E, Xianxun Zhu

Research Collection School Of Computing and Information Systems

Multimodal sentiment models often become over-reliant on the “easiest” modality (typically text), leading to three coupled sub-problems: (i) representation-level dominance, where weaker modalities contribute little to the fused representation; (ii) optimization-level dominance, where the strongest modality drives most gradient updates and suppresses learning in others; and (iii) robustness degradation, where audio or vision fail under noise or missing inputs at test time. We present TEMPO, a plug-and-play training framework that mitigates these issues by rebalancing learning pressure across modalities while leaving inference unchanged. For each mini-batch, TEMPO estimates relative modality strength and applies two synchronized, training-only controls: selective forward attenuation …


Nondeterministic Polynomial-Time Problem Challenge: An Ever-Scaling Reasoning Benchmark For Llms, Chang Yang, Ruiyu Wang, Junzhe Jiang, Qi Jiang, Qinggang Zhang, Yanchen Deng, Shuxin Li, Shuyue Hu, Bo Li, Florian T. Pokorny, Xiao Huang, Xinrun Wang Jan 2026

Nondeterministic Polynomial-Time Problem Challenge: An Ever-Scaling Reasoning Benchmark For Llms, Chang Yang, Ruiyu Wang, Junzhe Jiang, Qi Jiang, Qinggang Zhang, Yanchen Deng, Shuxin Li, Shuyue Hu, Bo Li, Florian T. Pokorny, Xiao Huang, Xinrun Wang

Research Collection School Of Computing and Information Systems

Reasoning is the fundamental capability of large language models (LLMs). Due to the rapid progress of LLMs, there are two main issues of current benchmarks: i) these benchmarks can be crushed in a short time (less than 1 year), and ii) these benchmarks may be easily hacked. To handle these issues, we propose the ever-scalingness for building the benchmarks which are scaling over complexity against crushing, instance against hacking and exploitation, oversight for easy verification, and coverage for real-world relevance. This paper presents Nondeterministic Polynomial-time Problem Challenge (NPPC), an ever-scaling reasoning benchmark for LLMs. Specifically, the NPPC has three main …


Voltage Stability Enhancement Of Large Load Interconnections Using Syncronous Condensers, Muhammad Ibrahim Abbas Jan 2026

Voltage Stability Enhancement Of Large Load Interconnections Using Syncronous Condensers, Muhammad Ibrahim Abbas

Graduate Studies Theses and Dissertations 2026

The rapid integration of hyperscale data centers as large, concentrated loads presents a growing voltage stability challenge in grids weakened by synchronous generator retirement and increasing inverter-based resource penetration. This work proposes a Jacobian-based sensitivity framework for systematically identifying voltage-critical buses and optimally siting synchronous condensers as voltage support resources. A voltage-weighted sensitivity index, extracted from the full Jacobian inverse, is introduced to combine network-wide reactive coupling strength with observed voltage drops into a single deployable placement criterion. Validation on IEEE 14-bus and 30-bus test systems under multiple loading scenarios demonstrates that the proposed criterion consistently identifies the correct placement …


An Analysis Of The Influence Of Project-Based Assessments In Middle School Mathematics, Andrea Fettkether Jan 2026

An Analysis Of The Influence Of Project-Based Assessments In Middle School Mathematics, Andrea Fettkether

Dissertations and Theses @ UNI

In today’s diverse classrooms, teachers face the challenge of educating students with varied academic abilities, including those with disabilities, gifted learners, and students at grade level. The Individuals with Disabilities Education Act (IDEA) ensures inclusive access to core curriculum, but educators must differentiate instruction to meet all learners’ needs. Traditional assessments focus on rote memorization, often failing to reflect deeper understanding or real-world problem-solving.

In middle school math, standard curricula often lack project-based assessments, despite research supporting their effectiveness in improving academic achievement and student engagement. Students benefit from working in collaborative environments where they can discuss mathematical ideas, receive …


Robust Linking Estimation In Item Response Theory Using Quantile Regression: Applications To The Graded Response And Generalized Partial Credit Models, Ibrahim Almansour Jan 2026

Robust Linking Estimation In Item Response Theory Using Quantile Regression: Applications To The Graded Response And Generalized Partial Credit Models, Ibrahim Almansour

Graduate Studies Theses and Dissertations 2026

This dissertation investigates robust estimation of linking coefficients in Item Response Theory (IRT) using quantile regression and its extensions. Linking procedures are essential for placing item and ability parameters from different test forms onto a common scale, thereby ensuring comparability of examinee scores across administrations. Traditional approaches such as moment methods, characteristic curve methods, and mean-based regression procedures like Ordinary Least Squares (OLS) and Generalized Least Squares (GLS) perform adequately under ideal conditions but tend to lose accuracy when ability distributions deviate from normality or include outliers.

To address these limitations, this research proposes a quantile-based regression framework that estimates …


Restoring Digital Trust: Decentralized Frameworks For Identity, Consent, And Media Provenance, Raghu N. Avula Jan 2026

Restoring Digital Trust: Decentralized Frameworks For Identity, Consent, And Media Provenance, Raghu N. Avula

Graduate Studies Theses and Dissertations 2026

Digital platforms are deeply embedded in modern society through centralized network architectures. As online interactions transition to the physical world handling sensitive data, user privacy and cryptographic security require enhancement beyond traditional limits. This dissertation presents a decentralized “Tri-Layer Trust Architecture” that leverages Verifiable Trust Registries, Cryptographic Binding, and Edge Verification to prioritize data sovereignty and local authentication. To demonstrate the architecture’s applicability across distinct operational environments, we implement three solutions: (1) Verifiable Presence for peer-to-peer ride-sharing via D-RideX, which encrypts biometric data on physical hardware (TEEs) and Soulbound Tokens (SBTs) to prevent impersonation without cloud database exposure; (2) Verifiable …


Learning-Based Optimization For Collaborative Truck-Drone Routing And Scheduling, Ahmad A. Bany Abdelnabi Jan 2026

Learning-Based Optimization For Collaborative Truck-Drone Routing And Scheduling, Ahmad A. Bany Abdelnabi

Graduate Studies Theses and Dissertations 2026

Modern delivery networks increasingly rely on innovative technologies such as drones working alongside trucks to meet rising demands for fast and efficient last–mile transportation. Hybrid truck–drone delivery offers strong potential, but its effectiveness depends on careful synchronization between trucks and drones. Although drones provide fast, direct travel, their limited endurance and the need to coordinate launch and recovery with trucks create tightly coupled routing and scheduling interactions. Poor dispatch decisions can cause truck waiting, reduce parallelism, and increase mission completion time. These challenges motivate decision frameworks that explicitly model synchronization and develop scalable methods for coordinated truck–drone operations. This dissertation …


An Integrated Framework For Last-Mile Delivery Optimization Using Reinforcement Learning And Social Media-Based Traffic Prediction In Underdeveloped Megacities, Vasanth Bhat Jan 2026

An Integrated Framework For Last-Mile Delivery Optimization Using Reinforcement Learning And Social Media-Based Traffic Prediction In Underdeveloped Megacities, Vasanth Bhat

Graduate Studies Theses and Dissertations 2026

Supply chain management has become increasingly critical as transportation costs rise and urban delivery systems place additional pressure on already congested networks. Last-mile delivery—the movement of goods from distribution centers to end users—represents the most expensive and operationally complex segment of the logistics process, particularly in underdeveloped megacities characterized by unpredictable traffic, limited infrastructure, and sparse real-time data. This dissertation proposes an integrated framework for optimizing last-mile delivery in such environments by combining social media–based traffic intelligence, machine learning, and deep reinforcement learning. The framework leverages unstructured, real-time data from social media platforms to enhance traffic prediction and incorporates these …


Investigation Of Exotic Phenomena In Topological Quantum Materials, Iftakhar Bin Elius Jan 2026

Investigation Of Exotic Phenomena In Topological Quantum Materials, Iftakhar Bin Elius

Graduate Studies Theses and Dissertations 2026

he First Quantum Revolution established quantum mechanics as the foundation of modern physics, enabling transformative technologies such as semiconductors, lasers, and transistors through prin-ciples of quantization, wave-particle duality, and uncertainty. The ongoing Second Quantum Rev-olution harnesses entanglement, superposition, and coherence to advance quantum computation, communication, simulation, and sensing. Central to this endeavor is the study of quantum mate-rials hosting novel electronic structures and emergent phases, including topological insulators and Dirac, Weyl, and nodal-line semimetals. In this thesis, using angle-resolved photoemission spec-troscopy (ARPES), transport measurements, and density functional theory (DFT) calculations, we investigate three classes of materials: (i) magnetic topological semimetals, …


Computational Modeling Of Bubble Dispersion In Alginate Hydrogel Foams For Radiologically Equivalent Biomedical Phantoms, Godson N. Brako Jan 2026

Computational Modeling Of Bubble Dispersion In Alginate Hydrogel Foams For Radiologically Equivalent Biomedical Phantoms, Godson N. Brako

Graduate Studies Theses and Dissertations 2026

The foaming of hydrogels presents a promising strategy for tailoring mechanical and radiological properties to replicate biological soft tissues for biomedical phantoms. Achieving uniform and predictable void fraction distributions in alginate hydrogel foams remains a challenge due to the complex interplay between bubble dynamics, matrix rheology, and interfacial forces during the pre-gelation aeration stage. This thesis develops a Computational Fluid Dynamics framework using the transient Eulerian two-fluid approach to predict void fraction distribution in alginate hydrogel precursor solutions aerated by air injection through a bottom nozzle. The objective is to use the framework for design of the foaming system to …


Detection And Discrimination Of Targets In Infrared Imagery, Adam T. Cuellar Jan 2026

Detection And Discrimination Of Targets In Infrared Imagery, Adam T. Cuellar

Graduate Studies Theses and Dissertations 2026

Automated infrared (IR) imagery analysis is essential for persistent surveillance, defense, and security, yet it remains difficult when sensors move and when unknown objects appear. This dissertation addresses two fundamental problems: (1) detecting small moving targets amid platform-motion induced parallax and (2) distinguishing between known stationary targets and out-of-distribution (OOD) objects.   For detecting moving targets while the platform itself is in motion, auxiliary Global Positioning System and Inertial Navigation System data are combined with image analysis. Direction Cosine Matrices from calibrated inertial measurements enable sub-pixel frame alignment unattainable with purely image-based registration. The stabilized sequence is processed by a Reed–Xiaoli …


Temperature And Speciation Measurements Of Aluminum-Laden Detonation Flows Via A Three-Color Wavelength Modulation Spectroscopic Sensor, Marc B. Etienne Jan 2026

Temperature And Speciation Measurements Of Aluminum-Laden Detonation Flows Via A Three-Color Wavelength Modulation Spectroscopic Sensor, Marc B. Etienne

Graduate Studies Theses and Dissertations 2026

Tunable diode lasers are widely used and are known to be great options for continuous wave lasing applications. Because of their stability and spectral selectivity, they have become an important diagnostic tool for modern combustion research. Previous combustion research, particularly those focused on solid and hybrid rocket systems, have shown that the interaction of aluminum with a reacting flow can greatly affect the dynamics and the thermochemical properties of the surrounding gas, therefore understanding the effects of aluminum-laden flows is critical for the advancement of these propulsion systems. However, due to the high degree of optical interference, high temperatures, and …


An Examination Of The Impact Of School Accountability On Data-Driven Decision-Making By Florida Educational Leaders, Emily Galucho Jan 2026

An Examination Of The Impact Of School Accountability On Data-Driven Decision-Making By Florida Educational Leaders, Emily Galucho

Graduate Studies Theses and Dissertations 2026

This mixed-methods study examined how accountability influences educational leaders' data-driven decision-making (DDDM) practices in Central Florida. Grounded in the principal-agent and consequential accountability frameworks, the study investigated demographic predictors, implementation challenges, and the role of accountability in DDDM. Educational leaders completed online surveys measuring DDDM perceptions across five subscales and responded to open-ended questions. The responses were analyzed through multiple regression, correlation, and thematic coding.

Accountability emerged as DDDM's strongest predictor, significantly exceeding demographic and organizational variables. Five implementation challenges were identified: Data Literacy Gaps, Data Timeliness Issues, Resource Constraints, Implementation Fidelity, and Systemic Barriers. Accountability demonstrated dual effects: many …


Reflection In Still Waters: Generative Ai's Production Of Language, Jonathan D. Hawks Jan 2026

Reflection In Still Waters: Generative Ai's Production Of Language, Jonathan D. Hawks

Graduate Studies Theses and Dissertations 2026

Language is a conceptual process of meaning-making as well as a social construction as defined by Saussure, Bakhtin, and Lacan. Large Language Models (LLMs) engage with neither process and instead present language as a finished and consumable product which undermines its fundamental aspects. The difference between representing language through probability and its structural components instead of its more inherent qualities is not a pointless distinction. This paper utilizes Narcissus as a central metaphor to show how people misread the outputs of LLMs as language which imparts to those reflected words meaning on par with our own conceptualizations of reality. People …


Predicting Safety And Mobility Parameters Based On Comprehensive Analytics Of Connected Vehicle Data, Lei Han Jan 2026

Predicting Safety And Mobility Parameters Based On Comprehensive Analytics Of Connected Vehicle Data, Lei Han

Graduate Studies Theses and Dissertations 2026

Traffic safety and mobility remain critical challenges for modern transportation systems. The emergence of connected vehicle (CV) data offers unprecedented opportunities to capture microscopic, non-aggregated driving dynamics to support precise and finer-grained traffic safety and mobility research. This dissertation develops a comprehensive CV data–driven analytical framework to advance traffic safety and mobility research across multiple roadway contexts, including intersections, segments, freeways, and urban arterial networks. For traffic safety, this research extracts both longitudinal and lateral risky driving behaviors from CV trajectories and integrates them with macro-level roadway, traffic, and visual environment features. A spatial machine learning framework is proposed for …


Benchmarking And Advancing Heterogeneous Data Reasoning With Large Language Models, Yebowen Hu Jan 2026

Benchmarking And Advancing Heterogeneous Data Reasoning With Large Language Models, Yebowen Hu

Graduate Studies Theses and Dissertations 2026

Large language models (LLMs) increasingly face complex real-world tasks requiring complex reasoning over heterogeneous inputs, including text, numbers, and structured data. This dissertation first investigates the capability boundaries of LLMs under such scenarios. Through the MeetingBank and SportsMetrics benchmarks, we show that while LLMs exhibit linguistic fluency, they struggle with factual accuracy, information density, and quantitative cross-referencing in meeting summarization and sports analysis. Using DecipherPref, a pair-wise evaluation framework grounded in the Bradley-Terry-Luce model, we further probe LLMs' inherent preferences for information-rich and lengthy inputs, and we identify critical deficiencies in financial decision-making through DeFine, where models lack precise insight …


Odd Colorings Of Graphs With Maximum Degree And Surface Conditions, Matthew Kyle Jan 2026

Odd Colorings Of Graphs With Maximum Degree And Surface Conditions, Matthew Kyle

Graduate Studies Theses and Dissertations 2026

A proper vertex coloring of a graph is said to be odd if, for each vertex, there is a color that is present an odd number of times in its neighborhood. Introduced as a softening of other coloring problems, this problem has recently seen much research interest. It has been conjectured that all planar graphs are odd-5-colorable. Further research has suggested bounds for odd coloring numbers of graphs with different maximum degree conditions, different girths, and on different surfaces; we progress results in all of these areas. We improve an upper bound for odd coloring numbers of graphs of maximum …


Cfd Investigation Of Heat Transfer Enhancement In Pipes Using Gyroid Tpms Structures For Industrial Steam Generation, Alejandro Moreno Escribano Jan 2026

Cfd Investigation Of Heat Transfer Enhancement In Pipes Using Gyroid Tpms Structures For Industrial Steam Generation, Alejandro Moreno Escribano

Graduate Studies Theses and Dissertations 2026

Industrial heating processes account for nearly 28\% of global CO2 emissions, and fossil fueled boilers predominate in high temperature applications. Industrial electrification can be an effective solution when combined with renewable energy sources. Increasing steam generation efficiency and at the same time maintaining system compactness is a significant challenge in industrial thermal processes. Traditional smooth pipes offer limited heat transfer surface area, which constrains boiling heat transfer performance and reduces the overall efficiency of steam generation systems. Advanced internal geometries have the potential to significantly enhance heat transfer by increasing surface area and promoting fluid mixing. This work presents a …


Revolution In The Age Of Social Media: A Mathematical Model For Information, Dissent, And Stability, Killian Muollo Jan 2026

Revolution In The Age Of Social Media: A Mathematical Model For Information, Dissent, And Stability, Killian Muollo

Graduate Studies Theses and Dissertations 2026

Revolutions, defined by Skocpol as rapid transformations in class, state, and/or social structures, are important world events that can cause civil wars, spark international trends, and result in transitions toward democratic and autocratic regimes alike. They are characterized largely by the mechanism of mass mobilization, which is increasingly facilitated by online networks and digital communication. In this dissertation, we investigate such means and outcomes of revolutions as dynamical systems. We construct three models describing separate but complementary aspects of revolution, beginning at the smallest unit of analysis and then moving outward in scope. First, we construct a graph-based model to …


A Theoretical Study Of Molecular Photoionization: Applications To Molecules Of Astrophysical And Atmospheric Interest, Conner Penson Jan 2026

A Theoretical Study Of Molecular Photoionization: Applications To Molecules Of Astrophysical And Atmospheric Interest, Conner Penson

Graduate Studies Theses and Dissertations 2026

This thesis is devoted to the development of the model for total molecular photoionization spectra which is general to diatomic molecules and the application of this model to two benchmark systems, CH and N2, for verification. This model combines multi-channel quantum defect theory, first-principles ab initio molecular calculations, and vibrational frame transformation to accurately model molecular photoionization and electron impact including vibrational dynamics. The scattering data and transition dipole moments for the molecular systems were calculated using R-matrix method through the UKRMol+ codes. A vibrational frame transformation is then performed and multi-channel quantum defect theory is used to calculate closed …


Adaptability And Applications Of Advanced Laser Absorption Diagnostics In High-Pressure Shock Tube Environments, Lucas R. Pitts Jan 2026

Adaptability And Applications Of Advanced Laser Absorption Diagnostics In High-Pressure Shock Tube Environments, Lucas R. Pitts

Graduate Studies Theses and Dissertations 2026

Theoretical application and physical implementation of various laser absorption spectroscopy (LAS) diagnostics are examined within a high-pressure shock tube facility. Research focuses on the rationale behind the specific optical alignment layouts used across three distinct experimental campaigns, detailing the methodology required to maintain signal integrity in varied reacting flow environments. The first research campaign addresses the pyrolysis of hydroxyl terminated polybutadiene (HTPB) solid propellant binders for solid fuel ramjet (SFRJ) applications by measuring the species time histories of alkenes and aromatics. Alignment configurations prioritized beam stability and signal strength for the decoupling of overlapping absorption features to ensure measurements accurately …


Study Of Compressibility Of Flames In Scramjet Combustors, Anirudh Ranganathan Jan 2026

Study Of Compressibility Of Flames In Scramjet Combustors, Anirudh Ranganathan

Graduate Studies Theses and Dissertations 2026

Viable forms of propulsion for practical hypersonic flight are of great interest in modern times, of which supersonic combustion ramjets(scramjets) are a very advantageous option. Compared to ramjets, which are severely limited by increasing total pressure loss and dissociation effects, scramjets offer a much more efficient form of propulsion in the Mach 6 – 8 regime. Despite this, a common and unmitigated issue facing scramjet technology is scramjet unstart.

Prior investigations researching scramjet unstart have elucidated global heat release considerations in relation to total fueling or combustion modes as a result of global heat release . Minimal work has been …


Old Maps Of The New World & New Theories On The European Encounter With La Florida: An Historical Archaeological And Four Field Anthropological Approach To Peter Apian's Cosmographia (1575), Emerson S F Richards Jan 2026

Old Maps Of The New World & New Theories On The European Encounter With La Florida: An Historical Archaeological And Four Field Anthropological Approach To Peter Apian's Cosmographia (1575), Emerson S F Richards

Graduate Studies Theses and Dissertations 2026

This thesis examines the 1575 Spanish edition of the Cosmographia, a geographic textbook initially authored by Peter Apian and expanded by Gemma Frisius, as a source for anthropological inquiry into early European encounters with the Americas. Little attention has been given to the text’s potential as a source for anthropological analysis, particularly regarding its representations of the Americas and the cultural information embedded in the geographic data. This study addresses that gap by applying a Four-Field anthropological framework—cultural, biological, linguistic, and archaeological—to this edition, which incorporates excerpts from Ieronimo Girava’s qualitative and quantitative description of the Americas, including a …


Shock Tube Speciation Analysis Of Hydrocarbon Mixtures Relevant To Solid Fuel Combustion, Diego N. Ruiz Pena Jan 2026

Shock Tube Speciation Analysis Of Hydrocarbon Mixtures Relevant To Solid Fuel Combustion, Diego N. Ruiz Pena

Graduate Studies Theses and Dissertations 2026

Solid Fuel Ramjets (SFRJs) are often used in tactical applications due to their simplicity, robustness, and reliability. No moving parts, atmospheric oxidizer usage, and scalable fuel grain designs make them a great solution for compact, high-speed air-breathing propulsion systems. SFRJs operate by compressing incoming air through a fixed geometry inlet and directing it over a regressing solid fuel surface, where pyrolysis gases are released and transported downstream to the combustion chamber where thrust is generated. Hydroxyl-terminated polybutadiene (HTPB) is a commonly used fuel binder in SFRJ systems due to its high energy density, stable combustion behavior, and ease of processing. …


Data-Driven Seismic Site Classification Using Earthquake And Microtremor Horizontal-To-Vertical Spectral Ratios, Sanidhya Sharma Jan 2026

Data-Driven Seismic Site Classification Using Earthquake And Microtremor Horizontal-To-Vertical Spectral Ratios, Sanidhya Sharma

Graduate Studies Theses and Dissertations 2026

The prevailing seismic site classification parameter, the time-averaged shear-wave velocity in the upper 30 meters (VS30), provides an incomplete representation of site conditions, neglecting deeper geology, impedance contrasts, and resonance phenomena. This thesis developed and validated a data-driven framework for seismic site classification based on the full spectral shape of Horizontal-to-Vertical Spectral Ratio (HVSR) curves combined with unsupervised machine learning, through two complementary research studies. Research 1 applied K-means clustering to earthquake-based HVSR (eHVSR) data from 3,186 ground motion stations across California and adjacent regions, identifying four physically distinct site clusters, characterized by low-frequency, very-low-frequency, high-frequency, and …


Evaluation Of Chromium-Crosslinked Amps-Hpam Copolymer Gels: Effects Of Key Parameters On Gelation Time And Strength, Maryam Sharifi Paroushi, Baojun Bai, Thomas P. Schuman, Yin Zhang, Mingzhen Wei Jan 2026

Evaluation Of Chromium-Crosslinked Amps-Hpam Copolymer Gels: Effects Of Key Parameters On Gelation Time And Strength, Maryam Sharifi Paroushi, Baojun Bai, Thomas P. Schuman, Yin Zhang, Mingzhen Wei

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Controlling CO2 channeling in heterogeneous reservoirs remains a major challenge for both enhanced oil recovery (EOR) and secure geological storage. AMPS-HPAM copolymers exhibit high-temperature resistance and brine tolerance compared with conventional HPAM gels, making them well suited for the harsh environments associated with CO2 injection. Chromium-based crosslinkers (CrAc and CrCl3) were investigated because sulfonic acid groups in AMPS can coordinate with trivalent chromium ions, enabling dual ionic crosslinking and the formation of a robust gel network. While organic crosslinked AMPS-HPAM gels have been widely studied, the behavior of chromium-crosslinked AMPS-containing systems, particularly their gelation kinetics under …


Effect Of Ionic Strength On Gelation Time And Strength Of Amps-Based Polymer Gels, Maryam Sharifi Paroushi, Xuyang Tian, Baojun Bai, Thomas P. Schuman, Yin Zhang, Mingzhen Wei Jan 2026

Effect Of Ionic Strength On Gelation Time And Strength Of Amps-Based Polymer Gels, Maryam Sharifi Paroushi, Xuyang Tian, Baojun Bai, Thomas P. Schuman, Yin Zhang, Mingzhen Wei

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Polymer gel treatment has been widely applied for improving sweep efficiency and controlling excessive water and gas production. Their performance depends on gelation time and final gel strength. In most studies, brine salinity is used to describe the effect of formation water on gel behavior. However, changing salinity also changes ionic strength and ion composition at the same time. Because of this coupling, it is difficult to identify the mechanisms controlling gelation, which has led to inconsistent trends in the literature. Increasing salinity has been reported to either slow or accelerate gelation and to weaken or strengthen gels depending on …


Solubility And Dissolution Mechanism Of Novel Multi-Ester Headgroup Surfactants In Supercritical Co2, Ning Xu, Yan Ling Wang, Baojun Bai, Shi Zhang Cui, Yu Zhang, Wen Jing Shi, Zhao Nian Zhang, Wen Hui Ding, Pei Xu Ma, Zan Gao Jan 2026

Solubility And Dissolution Mechanism Of Novel Multi-Ester Headgroup Surfactants In Supercritical Co2, Ning Xu, Yan Ling Wang, Baojun Bai, Shi Zhang Cui, Yu Zhang, Wen Jing Shi, Zhao Nian Zhang, Wen Hui Ding, Pei Xu Ma, Zan Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

To address the limited solubility and applicability of conventional hydrocarbon surfactants in supercritical CO2, a series of multi-ester headgroup surfactants were designed and synthesized by leveraging the CO2-philic properties of ester groups. The molecular structures were characterized using Fourier transform infrared (FT-IR) spectroscopy and 1H NMR. A custom-designed laser-based apparatus was developed to quantify surfactant solubility and systematically investigate phase behavior in CO2. Molecular dynamics (MD) simulations were employed to elucidate structure–solubility relationships across multiple scales, including solubility parameters, interaction energies, radial distribution functions (RDFs), and free volume fractions. Results indicate that, at 323.15 K, …


A Knowledge-Driven, Ai-Assisted Cyber Defence Framework For Iomt Remote Patient Monitoring, Kulsoom S. Bughio, David M. Cook, Abdul M. Unar Jan 2026

A Knowledge-Driven, Ai-Assisted Cyber Defence Framework For Iomt Remote Patient Monitoring, Kulsoom S. Bughio, David M. Cook, Abdul M. Unar

Research outputs 2022 to 2026

The rapid adoption of Internet Medical Things (IoMT) technologies in remote patient monitoring has reshaped healthcare delivery by enabling continuous, real-time clinical observation outside traditional care settings. However, this shift has also expanded the cyber-attack surface across heterogeneous, resource-constrained medical devices, wireless networks, cloud services, and third-party platforms. In cyber warfare, healthcare has become an incorporated target of geopolitics, with hospitals, remote monitoring systems, and emergency health systems being used to broaden the attack surface for adversaries to exploit. Existing security approaches for IoMT environments remain largely manual, fragmented, and reactive, limiting their effectiveness in dynamically assessing vulnerabilities and supporting …